1. Field of the Invention
This invention relates generally to roll-fed copying machines and, more particularly, to the apparatus and control circuitry for dispensing cut lengths from a roll of copy sheet material in accordance with varying size originals and wherein a switch responsive to the presence or absence of an original and a manually selected position is used in the control circuitry.
2. Description of the Prior Art
Roll-fed copy machines are known which use one or more switches that are operated in accordance with the presence or absence of original sheets fed into the machine and/or the presence or absence of copy paper for controlling the movement of copy sheet material from a supply and the cutting of the material to length corresponding to the length of the originals. U.S. Pat. No. 4,265,153 issued to Price and assigned to the assignee of the present application, discloses an electrically operated copy machine having a transferring mechanism driven by a drive motor for providing synchronous movement in the copy machine of copy paper and original sheets of varying lengths. The copy paper for the machine is provided by a continuous web of copy paper from a copy paper supply roll. U.S. Pat. No. 4,265,153 provides apparatus and circuitry used in the copy machine which is responsive to the presence and absence of the original sheet for cutting sheets from the copy paper which correspond to the length of the original and includes first and second copy paper feed rollers which are a part of the transferring mechanism. The first feed roller is positioned along the path of travel of the copy paper between the copy paper supply roll and the second feed roller. A solenoid operated cutter is positioned between the first and second feed rollers.
A solenoid controlled clutch is used for operatively connecting the first feed roller to the drive motor. The solenoid is energized only for the time necessary to have the first feed roller move the copy paper from an initial position at the cutter to the second feed roller which then continues to draw copy paper from the copy paper supply roll. Energization of the solenoid for the clutch and the solenoid for the cutter are controlled by a single switch which is positioned along the path of travel of an original sheet presented to the copy machine. The switch has a first and second position, the first position being provided when an original sheet is not presented to the switch with the second position provided when an original sheet is presented to the switch. The first position for the switch is used to complete a first circuit loop which includes a capacitor and the winding of the cutter solenoid. The second position of the switch completes a second circuit loop which includes the winding of the clutch solenoid, the capacitor and a D.C. power supply. Accordingly, the clutch solenoid is operated by the current flow for charging the capacitor when the leading edge of an original is initially detected by the switch to place it in its second position to complete the second circuit loop. The armature of the clutch solenoid is released as the current flow diminishes as the capacitor reaches full charge. When the trailing edge of the original sheet passes the switch, the switch moves to its first position which completes the first circuit loop that includes the capacitor, which is charged, and the winding of the cutter solenoid. This causes the cutter to be operated by discharge of the capacitor via the winding of the cutter solenoid. Accordingly, the cutter solenoid is operated to cut the copy paper to the length of the original sheet presented to the copy machine.
While the foregoing arrangement is entirely effective when the copy machine is used to make copies of standard sized originals, such is not the case when it is desired to make copies of extended length original documents. Since the copy machine is provided with a continuous web of copy paper, it is possible to make copies of documents such as oil well logs or electrocardiagrams which may exceed 100 feet in length. However, it is not always necessary to copy the entire length of such an original document and at times it would be desirable to copy selected, but separated, lengths of such a document onto a continuous sheet of copy paper.
Accordingly, it would be desirable to provide a copy machine such as that described above with means for interrupting the copying of an extended length original and either cutting the copy paper at that point or repositioning the original and continuing copying onto a single sheet of copy paper from the point of interruption.